Handheld vacuum cleaner



FIG. 1 is a front perspective view of a handheld vacuum cleaner which embodies our design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right side view thereof, the left side view thereof being a mirror image of the left side view thereof;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view thereof.

The details shown in broken lines forms no part of the claimed design. 

The ornamental design for a handheld vacuum cleaner, as shown and described. 